WO2019059099A1

WO2019059099A1 - Liquid discharge device, and liquid discharge head cleaning device and method

Info

Publication number: WO2019059099A1
Application number: PCT/JP2018/034035
Authority: WO
Inventors: 雄一尾崎; 琢磨中野
Original assignee: 富士フイルム株式会社
Priority date: 2017-09-25
Filing date: 2018-09-13
Publication date: 2019-03-28
Also published as: EP3689615A4; US20200215822A1; JPWO2019059099A1; JP6916887B2; EP3689615B1; US11247474B2; EP3689615A1

Abstract

Provided are a liquid discharge device and a liquid discharge head cleaning device and a method with which a nozzle surface is cleaned without any liquid penetrating into a gap between adjacent head modules of a liquid discharge head. A liquid discharge head (32) which discharges a liquid from a nozzle (202) disposed on a nozzle surface (33), wherein after performing a pressure purge, in which the inside of the liquid discharge head (32), which is constituted by a plurality of head modules (200) and in which gaps (G) exist between adjacent head modules, is pressurized to discharge liquid from the nozzle (202), a dry elongated wiping web (104) is caused to come into contact with the nozzle surface (33) of the liquid discharge head (32) with a pressing force of 0 kPa to 15 kPa, and then the wiping web (104) is transported in a web transport direction relative to the liquid discharge head (32) to wipe the nozzle surface (33).

Description

Liquid discharge device, liquid discharge head cleaning device and method

The present invention relates to a liquid discharge apparatus, a liquid discharge head cleaning apparatus and method, and more particularly, to a liquid discharge apparatus, a liquid discharge head cleaning apparatus, and a method for cleaning a liquid discharge head having a gap between adjacent head modules.

In the liquid discharge apparatus, if the nozzle surface of the liquid discharge head is contaminated by liquid residue or the like, there is a possibility that the nozzle formed on the nozzle surface may have a discharge failure. For this reason, it is necessary to periodically clean the nozzle surface.

As a method of cleaning the nozzle surface, a method of wiping the nozzle surface with a wiping member is known. Also, in order to always wipe the nozzle surface using the unused area of the wiping member, a long wiping web is used as the wiping member and the nozzle surface is wiped while conveying the wiping web. .

In Japanese Patent Application Laid-Open Publication No. 2008-101501, after the pressure purge for forcibly discharging the ink in the ink jet head from the nozzles is performed, the ink discharge surface (corresponding to the nozzle surface) is wiped with a wiping web in a dry state (corresponding to a dry state). Thereafter, a technique for wiping the ink ejection surface with a wiping web in a wet state (corresponding to a wet state) is described.

Patent Document 2 describes a technique for adjusting the pressing force of a pressing member that presses an endless sheet-like wiping member (corresponding to a wiping web) to the nozzle surface.

Further, Patent Document 3 describes a technique for adjusting a contact force with which a maintenance member (corresponding to a wiping web) contacts a discharge port forming surface (corresponding to a nozzle surface).

JP, 2015-039781, A JP, 2015-134448, A JP, 2017-043005, A

There is known a liquid discharge head formed by connecting a plurality of head modules. Such a liquid discharge head has a gap between adjacent head modules. If liquid gets into this gap, it may cause deterioration of head life and reliability, printing performance, and contamination of the recording medium.

When the pressure purge is performed as in the technique described in Patent Document 1, the liquid pressure-purged on the nozzle surface remains on the nozzle surface. Thereafter, when the nozzle surface is wiped with a wiping web, there is a problem that the liquid remaining on the nozzle surface infiltrates into the gap between the head modules.

However, the techniques described in Patent Documents 1 to 3 do not recognize the problem that the liquid intrudes into the gap between the head modules when wiping the nozzle surface.

The present invention has been made in view of such circumstances, and a liquid discharge apparatus for cleaning a nozzle surface without causing liquid to enter a gap between a liquid discharge head having a gap between adjacent head modules, and a liquid discharge head cleaning It is an object to provide an apparatus and method.

In order to achieve the above object, one aspect of the liquid discharge head cleaning apparatus is a liquid discharge head which discharges liquid from a nozzle disposed on a nozzle surface, which is constituted by a plurality of head modules and which are adjacent to each other A pressurized purge control unit that pressurizes the inside of the liquid discharge head having a gap between it and discharges the liquid from the nozzle, and after performing the pressure purge, the nozzle surface of the liquid discharge head is in a dry state A cleaning unit having a first wiping mode in which a long wiping web is brought into contact with a pressing force of 0 kPa or more and 15 kPa or less, and the wiping web is transported in the web conveyance direction to the liquid discharge head to wipe the nozzle surface And a liquid discharge head cleaning device.

According to this aspect, after the pressure purge is performed, the long wiping web in a dry state is brought into contact with the nozzle surface of the liquid discharge head with a pressing force of 0 kPa or more and 15 kPa or less, to the liquid discharge head. Since the wiping web is conveyed in the web conveyance direction to wipe the nozzle surface, the nozzle surface can be cleaned without the liquid entering the gap between the head modules.

The cleaning unit brings the elongated wiping web wet with the cleaning liquid into contact with the nozzle surface of the liquid ejection head with a pressing force of 20 kPa or more and 60 kPa or less, and conveys the wiping web against the liquid ejection head in the web conveyance direction. Preferably, a second wiping mode is provided to wipe the nozzle surface. Thereby, the nozzle surface can be cleaned properly.

The cleaning unit brings the wiping web in a dry state into contact with the nozzle surface of the liquid discharge head via the contact member with a pressing force of 0 kPa or more and 15 kPa or less, and moves the contact member relative to the liquid discharge head The dry wiping unit, which wipes the nozzle surface, and the nozzle surface of the liquid discharge head are brought into contact with the wet wiping web with a pressing force of 20 kPa or more and 60 kPa or less via the contact member to the liquid discharge head. The nozzle surface is wiped by the wet wiping unit which relatively moves the contact member to wipe the nozzle surface, and the drying wiping unit in the first wiping mode, and the nozzle surface is wiped by the wetting wiping unit in the second wiping mode Preferably, the cleaning control unit is provided. As a result, the nozzle surface can be cleaned without the liquid entering the gap between the head modules, and the nozzle surface can be properly cleaned.

The cleaning unit brings the wiping web into contact with the nozzle surface of the liquid discharge head via the contact member, moves the contact member relative to the liquid discharge head to wipe the nozzle surface, and the nozzle The pressing force adjustment unit that adjusts the pressing force between the surface and the wiping web, the cleaning solution deposition unit that applies the cleaning fluid to the dry wiping web to make it wet, and the cleaning fluid deposition unit does not operate in the first wiping mode The dry wiping web is brought into contact with the nozzle surface with a pressing force of 0 kPa or more and 15 kPa or less, and in the second wiping mode, the cleaning liquid is applied by the washing liquid application unit and the wet wiping web is pressed 20 kPa or more and 60 kPa or less Preferably, the cleaning control unit is brought into contact with the nozzle surface by pressure. As a result, the nozzle surface can be cleaned without the liquid entering the gap between the head modules, and the nozzle surface can be properly cleaned.

The cleaning unit includes an elastic member urging the contact member in the first direction toward the nozzle surface, and a support unit supporting the elastic member, and the cleaning control unit is configured to support the support unit and the support in the first wiping mode. The distance between the nozzle surface and the nozzle web in the first direction is set to a first distance at which the pressing force between the nozzle surface and the wiping web is 0 kPa or more and 15 kPa or less, and in the second wiping mode It is preferable to set the distance in the first direction to a second distance at which the pressing force between the nozzle surface and the wiping web is 20 kPa or more and 60 kPa or less. Thereby, the pressing force can be set appropriately.

The cleaning unit brings the elongated wiping web wet with the cleaning liquid into contact with the nozzle surface of the liquid ejection head with a pressing force of 20 kPa or more and 60 kPa or less, and conveys the wiping web against the liquid ejection head in the web conveyance direction. Have a third wiping mode for wiping the nozzle surface, and perform wiping in the second wiping mode after wiping in the first wiping mode and wiping in the third wiping mode after wiping in the second wiping mode Is preferred. Thereby, the nozzle surface can be cleaned properly.

In order to achieve the above object, one aspect of the liquid discharge head cleaning apparatus is a liquid discharge head which discharges liquid from a nozzle disposed on a nozzle surface, which is constituted by a plurality of head modules and which are adjacent to each other A long wiping web in a dry state is brought into contact with the nozzle surface of the liquid discharge head having a gap with a pressing force of 0 kPa or more and 15 kPa or less, and the wiping web is transported in the web conveyance direction with respect to the liquid discharge head The first wiping mode for wiping the nozzle surface, and a long wiping web in a wet state with the cleaning liquid is brought into contact with the nozzle surface of the liquid discharge head with a pressing force of 20 kPa or more and 60 kPa or less A cleaning unit having a second wiping mode in which the wiping web is conveyed in the web conveyance direction to wipe the nozzle surface; A selection unit for selecting one mode of the second wiping mode, a liquid discharge head cleaning device having a.

According to this aspect, the first wiping mode in which the long wiping web in the dry state is brought into contact with a pressing force of 0 kPa or more and 15 kPa or less and the long wiping web in the wet state by the cleaning liquid is 20 kPa or more and 60 kPa or less Since one of the second wiping modes to be brought into contact with the pressing force of the above is selected, the nozzle surface can be properly cleaned.

In order to achieve the above object, one aspect of the liquid ejection apparatus is a liquid ejection head which ejects liquid from a nozzle disposed on a nozzle surface, which is constituted by a plurality of head modules and is disposed between adjacent head modules A liquid ejection head having a gap, a conveyance unit for conveying a recording medium, a recording control unit for ejecting a liquid from a nozzle of the liquid ejection head to the conveyed recording medium, and recording an image on the recording medium A pressurized purge control unit for pressurizing the inside of the head and discharging pressurized liquid from the nozzles, and after performing pressurized purge, a long wiping web in a dry state on the nozzle surface of the liquid discharge head The first wiping is performed by bringing the wiping web into contact with the liquid ejection head in the web conveyance direction to wipe the nozzle surface by bringing the wiping web into contact with a pressure of 0 kPa or more and 15 kPa or less. A cleaning unit having a over de, a liquid ejecting apparatus having a.

The cleaning unit includes a plurality of liquid ejection heads that eject different colors of ink, and the cleaning unit is configured to press the pressure when wiping the liquid ejection head that ejects the black ink in the first wiping mode as ink other than the black ink. Preferably, the pressing force is smaller than the pressing force at the time of wiping the liquid discharge head that discharges the ink. This can extend the life of the nozzle surface of the liquid discharge head that discharges black ink.

In order to achieve the above object, one aspect of the liquid discharge head cleaning method is a liquid discharge head which discharges a liquid from a nozzle disposed on a nozzle surface, which is constituted by a plurality of head modules and which are adjacent to each other And a pressure purge step of pressurizing the inside of the liquid discharge head having a gap between them to discharge the liquid from the nozzle, and after performing the pressure purge, the nozzle surface of the liquid discharge head is in a dry state. A liquid discharge head comprising a cleaning step of contacting a long wiping web with a pressing force of 0 kPa or more and 15 kPa or less and conveying the wiping web against the liquid discharge head in the web conveyance direction to wipe the nozzle surface It is a cleaning method.

In order to achieve the above object, one aspect of the liquid discharge head cleaning method is a liquid discharge head which discharges a liquid from a nozzle disposed on a nozzle surface, which is constituted by a plurality of head modules and which are adjacent to each other A long wiping web in a dry state is brought into contact with the nozzle surface of the liquid discharge head having a gap with a pressing force of 0 kPa or more and 15 kPa or less, and the wiping web is transported in the web conveyance direction with respect to the liquid discharge head The first wiping mode for wiping the nozzle surface, and a long wiping web in a wet state with the cleaning liquid is brought into contact with the nozzle surface of the liquid discharge head with a pressing force of 20 kPa or more and 60 kPa or less A second wiping mode in which the wiping web is conveyed in the web conveyance direction to wipe the nozzle surface, and a cleaning process, and a first wiping mode A selection step of selecting one mode among the beauty second wiping mode, a liquid discharge head cleaning method comprising a.

According to the present invention, the nozzle surface can be cleaned without the liquid entering the gap between the head modules.

Front view of the inkjet recording apparatus Top view of inkjet recording apparatus Side view of inkjet recording device Configuration diagram of the head Partially enlarged view of Figure 4 Top view of the head module Schematic of nozzle surface wiping device Block diagram showing control system of ink jet recording apparatus Flow chart showing processing of head cleaning method Schematic showing the dry wipe Schematic showing wet wipes Front view of the inkjet recording apparatus

Hereinafter, preferred embodiments of the present invention will be described in detail with reference to the attached drawings.

<Ink jet recording apparatus>
1 to 3 are a front view, a plan view, and a side view showing the configuration of the main part of the ink jet recording apparatus 10 according to the present embodiment, respectively.

The inkjet recording apparatus 10 (an example of a liquid ejection apparatus, an example of a liquid ejection head cleaning apparatus) is a single-pass line printer and mainly includes a sheet conveyance unit 20 for conveying a sheet P, which is a recording medium, and a plurality of inkjets A head unit 30 including

heads

32C, 32M, 32Y, and 32K, a head moving unit 36 (see FIG. 8) for moving the head unit 30, and a maintenance unit for maintaining the

inkjet heads

32C, 32M, 32Y, and 32K And a nozzle surface cleaning unit 80 for wiping and cleaning the nozzle surfaces of the

inkjet heads

32C, 32M, 32Y, and 32K provided in the head unit 30.

The sheet conveyance unit 20 conveys the sheet P by causing the traveling belt 22 to adsorb the sheet P. The travel route is set so that the belt 22 travels horizontally at a part of the location. The sheet conveyance unit 20 horizontally conveys the sheet P using a portion where the belt 22 travels horizontally. The sheet P is transported by the sheet transport unit 20 in the Y direction in a horizontal posture.

The

inkjet heads

32C, 32M, 32Y, and 32K respectively eject cyan ink droplets, magenta ink droplets, yellow ink droplets, and black (black) ink droplets. The

inkjet heads

32C, 32M, 32Y, and 32K are attached to the head support frame 34.

The

inkjet heads

32C, 32M, 32Y, and 32K are each a full line type inkjet head having a rectangular block shape and corresponding to the maximum sheet width of the sheet P to be printed.

The head support frame 34 is detachably attached to a head attachment portion (not shown) for attaching each head 32.

When each head 32 is attached to the head support frame 34, the nozzle surface 33 (see FIG. 4) is disposed parallel to the XY plane which is a horizontal plane, and orthogonal to the Y direction which is the conveyance direction of the sheet P. It is arranged at a constant interval along the Y direction.

Further, the head attachment portion is provided so that the position in the Z direction which is the vertical direction can be adjusted. The height position of the nozzle surface 33 is adjusted for each head 32 attached to the head attachment part by adjusting the position of the head attachment part in the Z direction.

The head moving unit 36 (see FIG. 8) horizontally moves the head unit 30 in the X direction orthogonal to the Y direction. The head moving unit 36 includes, for example, a ceiling frame installed horizontally across the sheet conveyance unit 20, a guide rail laid on the ceiling frame, a traveling body sliding on the guide rail, and a traveling body And drive means for moving along the guide rails. As a drive means, for example, a feed screw mechanism including a feed screw and a motor for rotationally driving the feed screw can be used. The head support frame 34 is attached to the traveling body, and the head unit 30 slides horizontally.

The inkjet heads 32C, 32M, 32Y, and 32K included in the head unit 30 are moved between the “image recording position” and the “maintenance position” by the head moving unit 36 driving the head unit 30 and moving horizontally. To move.

At the image recording position, the inkjet heads 32C, 32M, 32Y, and 32K face the sheet P conveyed by the sheet conveyance unit 20. The sheet P is conveyed horizontally by the sheet conveyance unit 20 along one direction. When the sheet P passes downward in the Z direction of the head unit 30, ink droplets are respectively ejected toward the sheet P from the inkjet heads 32C, 32M, 32Y, and 32K provided in the head unit 30. Thus, the image is recorded on the sheet P.

At the maintenance position, the inkjet heads 32C, 32M, 32Y, and 32K face the maintenance unit 50. The maintenance unit 50 is provided with

caps

52C, 52M, 52Y, and 52K that store the moisturizing liquid and cover the nozzle surfaces 33 of the inkjet heads 32C, 32M, 32Y, and 32K, respectively. The configuration of the

caps

52C, 52M, 52Y and 52K is similar.

When the inkjet heads 32C, 32M, 32Y and 32K are located at the maintenance position, they are located above the

caps

52C, 52M, 52Y and 52K in the Z direction. At the maintenance position, the maintenance control unit 160 (see FIG. 8) performs a maintenance operation of the inkjet heads 32C, 32M, 32Y, and 32K. As an example of the maintenance operation, preliminary ejection is performed by driving a piezoelectric element provided for each nozzle 202 (see FIG. 6) to eject ink not contributing to recording from the plurality of nozzles 202, and pressurizing the inside of the head 32 There is a pressurized purge that ejects the ink from the nozzle 202 of the

The

cap

52C, 52M, 52Y, and 52K have a suction mechanism (not shown) for sucking the nozzle 202, and a moisturizing liquid supply mechanism (not shown) for supplying a moisturizer to the

caps

52C, 52M, 52Y, and 52K. Etc. are provided. Further, the waste liquid tray 54 is disposed at a position in the Z direction downward of the

caps

52C, 52M, 52Y, and 52K. The moisturizing solution supplied to the cap 52 is discarded to the waste liquid tray 54, and is recovered from the waste liquid tray 54 to the waste liquid tank 58 through the waste liquid recovery pipe 56.

When stopping the device for a long time, etc., move the head unit 30 to the maintenance position, cover the nozzle faces 33 of the inkjet heads 32C, 32M, 32Y and 32K with the

caps

52C, 52M, 52Y and 52K, respectively, A moisturizing space is formed between 33 and the

caps

52C, 52M, 52Y and 52K. This prevents non-ejection due to drying.

The nozzle surface cleaning unit 80 is installed between the image recording position on the movement path of the head unit 30 and the maintenance position. The nozzle surface cleaning unit 80 includes a nozzle surface wiping unit 82 that wipes the nozzle surfaces 33 of the inkjet heads 32C, 32M, 32Y, and 32K.

The nozzle surface wiping unit 82 (an example of the cleaning unit) wipes the nozzle surfaces 33 when the inkjet heads 32C, 32M, 32Y, and 32K move between the image recording position and the maintenance position.

The nozzle surface wiping unit 82 includes nozzle

surface wiping devices

100C, 100M, 100Y, and 100K that individually wipe the nozzle surfaces 33 of the inkjet heads 32C, 32M, 32Y, and 32K included in the head unit 30. The nozzle

surface wiping devices

100C, 100M, 100Y, and 100K are installed on the common mount 84 in accordance with the installation intervals of the inkjet heads 32C, 32M, 32Y, and 32K.

The nozzle surface wiping unit 82 wipes each nozzle surface 33 at a wiping position for wiping each nozzle surface 33 when the ink jet heads 32C, 32M, 32Y, and 32K move to a position facing the nozzle surface wiping unit 82. It is configured to be movable by a moving mechanism (not shown) between the retracted position where it does not move.

<Structure of inkjet head>
The configurations of the inkjet heads 32C, 32M, 32Y, and 32K are the same, so in the following description, the head 32 will be described unless otherwise specified.

FIG. 4 is a block diagram of the head 32. As shown in FIG. The head 32 has a structure in which head modules 200-1 to 200-n are connected in the width direction (X direction) of the sheet P orthogonal to the conveyance direction (Y direction) of the sheet P. The configurations of the head modules 200-1 to 200-n are the same.

FIG. 5 is a partially enlarged view of FIG. 5, head module 200-i, head module 200-i, head module 200- (i-1) adjacent on the left side in FIG. 4, and head module 200- (i + 1) adjacent on the right side in FIG. It shows. As shown in FIG. 5, a gap G is provided between the head module 200-i and the head module 200- (i-1) (an example having a gap between the head modules). Similarly, a gap G is also provided between the head module 200-i and the head module 200- (i + 1). Thus, the head 32 has the gap G between the head modules 200 adjacent to each other.

FIG. 6 is a plan view of the head module 200-i. As shown in FIG. 6, a plurality of nozzles 202 are disposed on the nozzle surface 33 of the head module 200-i. Thus, the head 32 constitutes a full-line type inkjet head in which a plurality of nozzles 202 are arranged in a matrix over the length corresponding to the entire length in the X direction of the recording medium conveyed in the Y direction.

The head module 200-i has an end face on the long side along the V direction having an inclination of the angle β with respect to the X direction, and a short side along the W direction having an inclination of the angle α to the Y direction. It has a parallelogram planar shape consisting of an end face. In the nozzle surface 33, a plurality of nozzles 202 are arranged in the row direction along the V direction and the column direction along the W direction. The arrangement of the nozzles 202 is not limited to the mode shown in FIG. 6, and even if a plurality of nozzles 202 are arranged along the row direction along the X direction and the column direction diagonally intersecting with the X direction. Good.

In the head module 200-i in which the nozzles 202 are arranged in a matrix, the nozzles 202 are arranged at equal intervals in the X direction in a projection nozzle row in which the nozzles 202 are projected to be aligned in the X direction. That is, the X direction is the substantial arrangement direction of the nozzles, and the distance between the nozzles 202 in the projection nozzle row in the X direction is the recording resolution of the head 32 in the X direction.

Although not shown, the head module 200-i includes a pressure chamber in communication with the nozzle 202 and a supply flow path in communication with the pressure chamber via the supply port. When ink (an example of liquid) is discharged from the nozzle 202, the ink is filled from the supply flow path to the pressure chamber through the supply port.

As a method of ejecting the ink of the head 32, a piezoelectric method utilizing deflection deformation of a piezoelectric element may be applied, or a thermal method utilizing film boiling of ink may be applied. In the piezoelectric method, when a drive voltage is applied to the piezoelectric element, the volume of the pressure chamber is reduced according to the bending deformation of the piezoelectric element, and the ink corresponding to the volume reduction of the pressure chamber is discharged from the nozzle 202.

In the thermal method, the ink in the pressure chamber is heated to generate bubbles, and the ink corresponding to the volume of the pressure chamber is discharged from the nozzle 202.

A liquid repellent film having liquid repellency to the ink and a cleaning liquid described later is formed on the nozzle surface 33, and the entire surface of the nozzle surface 33 has liquid repellency. The contact angle between the nozzle surface 33 and the ink, and the contact angle between the nozzle surface 33 and the cleaning liquid are both 90 ° or more. The nozzle surface 33 is not limited to the aspect in which the entire surface has liquid repellency, but may be liquid repellent only in a necessary region of the nozzle surface 33 such as the vicinity of the nozzle 202.

<Nozzle surface cleaning unit>
The configurations of the nozzle

surface wiping devices

100C, 100M, 100Y, and 100K are the same. Therefore, in the following description, the nozzle surface wiping device 100 will be described unless otherwise specified.

FIG. 7 is a schematic view showing a schematic configuration of the nozzle surface wiping device 100. As shown in FIG. As shown in FIG. 7, the nozzle surface wiping apparatus 100 includes a web conveyance unit 102 that conveys the wiping web 104 in the web conveyance direction, and a cleaning liquid deposition unit 130 that supplies a cleaning liquid to the wiping web 104.

[Configuration of web conveyance unit]
The web transport unit 102 includes a supply shaft 106 for delivering the wiping web 104, a take-up shaft 108 for winding the wiping web 104, a pressing roller 110 for pressing the wiping web 104 against the nozzle surface 33 of the head 32, and a pressing roller. And a spring 114 for urging the pressing roller 110 in the upward direction of the Z direction (the direction of the nozzle surface 33, an example of the first direction), and the supply shaft 106 and the pressing roller 110. The first guide roller 116 for guiding the traveling of the wiping web 104 between the two, the second guide roller 118 for guiding the traveling of the wiping web 104 between the pressing roller 110 and the winding shaft 108, and the winding shaft 108 are rotated. And a take-up motor 120 for driving.

The wiping web 104 is made of an absorbable long sheet made of knitted or woven using ultrafine fibers such as polyethylene terephthalate, polyethylene, acrylic and the like. The width of the wiping web 104 corresponds to the width in the short direction of the nozzle surface 33 of the head 32 to be wiped, that is, the width in the direction orthogonal to the moving direction of the head 32, and the same or substantially the same width as the width It is.

The feed shaft 106 is rotatably supported by a shaft (not shown). The feed shaft 106 is disposed orthogonal to the moving direction of the head 32 and disposed horizontally. A reel (not shown) is detachably mounted on the supply shaft 106. The wiping web 104 is wound around the reel in a roll and attached to the supply shaft 106.

The wiping web 104 attached to the supply shaft 106 is in a dry state (non-washing liquid non-applied) in which the washing liquid is not applied.

The winding shaft 108 is rotatably supported by a shaft (not shown). The winding shaft 108 is disposed orthogonal to the moving direction of the head 32 and disposed horizontally. A reel (not shown) is detachably mounted on the winding shaft 108. The wiping web 104 is rolled up on a reel mounted on the winding shaft 108.

The pressure roller 110 (an example of the contact member) has a roller shape (cylindrical shape). The length in the direction (axial direction) orthogonal to the radial direction of the pressure roller 110 has a length corresponding to the width of the wiping web 104, and the size in the radial direction can be appropriately determined. The pressure roller 110 is rotatably and vertically movably supported in a state of being biased upward in the Z direction by a spring 114.

The pressure roller 110 is disposed orthogonal to the moving direction of the head 32 and disposed horizontally. The wiping web 104 is wound around the upper circumferential surface of the pressing roller 110, and pressed against the nozzle surface 33 of the head 32 via the pressing roller 110.

A support 112 (an example of a support portion) is connected to one end of the spring 114 (an example of an elastic member). Further, the pressing roller 110 is connected to the other end of the spring 114. Thus, the support 112 supports the pressing roller 110 via the spring 114. Further, the spring 114 biases the pressure roller 110 upward in the Z direction.

The head 32 that moves the position facing the pressing roller 110 by the head moving unit 36 is configured to be able to change the height in the Z direction when moving. Thus, the distance h between the support 112 and the nozzle surface 33 can be changed, and the pressing force between the wiping web 104 and the nozzle surface 33 can be adjusted. The relationship between the distance h and the pressing force is obtained by acquiring data in advance and storing the data in a memory (not shown).

The first guide roller 116 is rotatably supported by a horizontal shaft (not shown), and is disposed between the supply shaft 106 and the pressing roller 110 orthogonal to the moving direction of the head 32. The first guide roller 116 guides the wiping web 104 delivered from the supply shaft 106 toward the pressing roller 110.

The second guide roller 118 is rotatably supported by a horizontal shaft (not shown), and is disposed between the pressure roller 110 and the take-up shaft 108 orthogonal to the moving direction of the head 32. The second guide roller 118 guides the wiping web 104 whose wiping surface has been wiped by the pressing roller 110 toward the winding shaft 108.

A rotating shaft (not shown) is connected to the winding shaft 108, and the winding motor 120 rotationally drives the winding shaft 108 by rotating the rotating shaft. As the take-up shaft 108 rotates counterclockwise in the drawing, the wiping web 104 is conveyed from the supply shaft 106 toward the take-up shaft 108 and taken up on the take-up shaft 108.

[Configuration of the cleaning liquid deposition unit]
Under the control of the cleaning control unit 154 (see FIG. 8), the cleaning liquid deposition unit 130 brings the wiping web 104 in contact with the nozzle surface 33 into a wet state (cleaning liquid deposition state).

The cleaning solution deposition unit 130 includes a cleaning solution supply nozzle 132, a cleaning solution tank 134 for storing the cleaning solution, a cleaning solution flow path 136 connecting the cleaning solution supply nozzle 132 and the cleaning solution tank 134, and the cleaning solution supply nozzle 132 from the cleaning solution tank 134. And a washing solution pump 138 for feeding liquid.

The cleaning liquid deposition unit 130 drives the cleaning liquid pump 138 to supply the cleaning liquid from the cleaning liquid tank 134 to the cleaning liquid supply nozzle 132 via the cleaning liquid flow path 136.

The cleaning solution supply nozzle 132 has a jet having a width corresponding to the width of the wiping web 104, and the cleaning solution supplied from the cleaning solution tank 134 is sprayed from the jet toward the wiping web 104. When the wiping web 104 passes a position facing the cleaning liquid supply nozzle 132, the cleaning web is spouted from a jet and a cleaning liquid is applied. As a result, the cleaning liquid is absorbed inside the wiping web 104, and the wiping web 104 becomes wet.

The transport speed of the wiping web 104 by the web transport unit 102 and the application amount of the cleaning liquid supplied by the cleaning liquid application unit 130 are determined according to the penetration speed of the cleaning liquid in the wiping web 104. That is, the time for which the wiping web 104 is conveyed from the position facing the cleaning liquid supply nozzle 132 to the position of the pressing roller 110 is set longer than the time for the cleaning liquid supplied to the wiping web 104 to penetrate the wiping web 104. There is a need.

The nozzle surface wiping apparatus 100 configured in this way wipes the nozzle surface 33 with the dry wiping mode (an example of the first wiping mode) in which the nozzle surface 33 is wiped with the wiping web 104 in a dry state and the wiping web 104 in a wet state. And a wet wiping mode (an example of a second wiping mode) for wiping.

In the dry wiping mode, by stopping the application of the cleaning liquid by the cleaning liquid application unit 130, the wiping web 104 in contact with the nozzle surface 33 is brought into a dry state (non-cleaning liquid applied state). Further, in the wet wiping mode, the wiping web 104 in contact with the nozzle surface 33 is brought into a wet state (cleaning fluid applying state) by the cleaning solution applying unit 130.

<Control system of inkjet recording apparatus>
FIG. 8 is a block diagram showing a control system of the inkjet recording apparatus 10. The inkjet recording apparatus 10 includes a head movement control unit 150, an image recording control unit 152, a cleaning control unit 154, a maintenance control unit 160, and the like.

The head movement control unit 150 controls the head moving unit 36 to move the head 32 provided in the head unit 30 between the “image recording position” and the “maintenance position”.

Based on the image data to be recorded on the sheet P, the image recording control section 152 controls the sheet conveying section 20 and a piezoelectric element (not shown) for each nozzle 202 of the head 32 located at the image recording position to convey the sheet P. And discharge ink droplets of each color to record an image on the recording surface of the sheet P.

The cleaning control unit 154 controls the nozzle surface wiping unit 82 to wipe the nozzle surface 33 (see FIG. 4) of the head 32. The cleaning control unit 154 includes a selection unit 156 and a pressing force adjustment unit 158.

The selection unit 156 selects the dry wiping mode or the wet wiping mode.

The pressing force adjustment unit 158 adjusts the pressing force between the wiping web 104 and the nozzle surface 33 in accordance with the mode selected by the selection unit 156. The adjustment of the pressing force is performed by changing the distance h between the support table 112 and the nozzle surface 33. Here, the distance h is changed by adjusting the position of the support 112 in the Z direction, but the distance h may be changed by adjusting the position of the head 32 in the Z direction.

The maintenance control unit 160 supplies moisturizing fluid to the

caps

52C, 52M, 52Y, and 52K. Further, it controls a suction mechanism (not shown), a moisturizing fluid supply mechanism (not shown) and the like.

Further, the maintenance control unit 160 (an example of the preliminary ejection control unit) causes the nozzles 202 of the head 32 to perform preliminary ejection of the ink.

Further, the maintenance control unit 160 includes a pressure purge control unit 162. The pressure purge control unit 162 pressurizes the inside of the head 32 by a pressure unit (not shown) and discharges the ink from the nozzles 202 of the head 32.

<Liquid discharge head cleaning method>
FIG. 9 is a flowchart showing the process of the cleaning method of the head 32 by the inkjet recording apparatus 10.

In step S1, the inkjet heads 32C, 32M, 32Y, and 32K perform pressure purge toward the

caps

52C, 52M, 52Y, and 52K at the maintenance position (an example of a pressure purge process). The pressure purge is controlled by the pressure purge control unit 162 of the maintenance control unit 160. This pressure purge is performed to remove the ink whose viscosity has increased inside the nozzle 202.

When the pressure purge is completed, the head movement control unit 150 controls the head moving unit 36 to move the inkjet heads 32C, 32M, 32Y, and 32K from the maintenance position toward the image recording position. Here, the cleaning control unit 154 moves the nozzle surface wiping unit 82 of the nozzle surface cleaning unit 80 to the retracted position in advance, and the nozzle surfaces 33 of the inkjet heads 32C, 32M, 32Y, and 32K and the nozzle surface wiping unit 82 The nozzle

surface wiping devices

100C, 100M, 100Y, and 100K are not in contact with each other.

When the movement of the inkjet heads 32C, 32M, 32Y, and 32K is completed, the pressing force adjustment unit 158 of the cleaning control unit 154 moves the nozzle surface wiping unit 82 to the wiping position in step S2. Furthermore, for each nozzle

surface wiping device

100C, 100M, 100Y, and 100K, by changing the Z-direction position of the support 112 and adjusting the distance h (see FIG. 7) between the support 112 and the nozzle surface 33, The pressing force between the wiping web 104 and the nozzle surface 33 is adjusted.

Here, the pressing force between the wiping surface 104 of the nozzle

surface wiping apparatus

100C, 100M, and 100Y and the nozzle surface 33 of the inkjet heads 32C, 32M, and 32Y (an example of a liquid ejection head that ejects ink other than black ink). Is set to the first pressing force. A distance to be a first pressing force is a distance h ₁ (an example of a first distance). The pressing force adjustment unit 158 changes the position of the support base 112 of the nozzle

surface wiping apparatus

100C, 100M, and 100Y in the Z direction, and the support base 112 of the nozzle

surface wiping apparatus

100C, 100M, and 100Y and the

inkjet head

32C, 32M, and it sets the distance between the nozzle surface 33 of 32Y each distance _{h 1.}

Further, the pressing force adjusting unit 158 has a pressing force between the wiping web 104 of the nozzle surface wiping device 100K and the nozzle surface 33 of the ink jet head 32K (an example of a liquid ejection head for ejecting black ink) weaker than the first pressing force. Set to the third pressing force. Here, the distance to be the third pressing force is a distance h ₃ (an example of a third distance). The distance _{h 3} is greater than the distance _{h 1.} Pressing force adjusting unit 158 changes the position of the support 112 of the nozzle surface wiping device 100K, setting the distance between the support 112 and the nozzle surface 33 of the inkjet head 32K of the nozzle surface wiping device 100K to the distance _{h 3.}

Next, in step S3, the head movement control unit 150 controls the head moving unit 36 to move the inkjet heads 32C, 32M, 32Y, and 32K at a first speed from the image recording position to the maintenance position. Here, the first velocity is 5 mm / s (millimeters per second).

In step S4, the cleaning control unit 154 causes the web conveying unit 102 of the nozzle

surface wiping devices

100C, 100M, 100Y, and 100K to convey the wiping web 104, respectively. Here, the transport speed of the wiping web 104 is 3 mm / s. Further, the cleaning control unit 154 does not apply the cleaning liquid to the wiping web 104 (an example of non-operation), and keeps the wiping web 104 in a dry state. When the cleaning web is applied to the wiping web 104 in an amount of less than 10% of the amount of cleaning fluid that can be absorbed by the wiping web 104, it can also be regarded as the wiping web 104 in a dry state.

In this state, when the ink jet heads 32C, 32M, 32Y, and 32K reach the positions facing the nozzle

surface wiping devices

100C, 100M, 100Y, and 100K, the nozzle surfaces 33 are wiped by the wiping webs 104. That is, the nozzle surface 33 of the inkjet heads 32C, 32M, and 32Y is dry wiped by the first pressing force by the wiping web 104 in the dry state, and the nozzle face 33 of the inkjet head 32K is the wiping web 104 in the dry state. Dry wiping is performed by the third pressing force (an example of the first wiping mode, an example of the cleaning process).

FIG. 10 is a schematic view showing dry wiping. A large amount of ink droplets remain on the nozzle surface 33 of the head 32 due to the pressure purge in step S1. Therefore, the wiping web 104 in a dry state is wiped to absorb the ink droplets. It is important not to allow ink droplets to enter the gap G between the head modules 200 adjacent to each other.

To absorb the ink drop, the wiping web 104 may be in contact with the ink drop. For this reason, there is no need to apply a pressing force to the nozzle surface 33 in principle. If the pressing force on the nozzle surface 33 is too high, the ink absorbed by the wiping web 104 is squeezed out and pushed into the gap G between the head modules 200. Therefore, it is necessary to set the first pressing force and the third pressing force not to squeeze out the ink absorbed by the wiping web 104.

When the dry wiping is completed, the cleaning control unit 154 moves the nozzle surface wiping unit 82 to the retracted position, and the head movement control unit 150 directs the inkjet heads 32C, 32M, 32Y, and 32K from the maintenance position to the image recording position. Move it.

Subsequently, in step S5, the pressing force adjustment unit 158 of the cleaning control unit 154 moves the nozzle surface wiping unit 82 to the wiping position, and the support base 112 for each of the nozzle

surface wiping devices

100C, 100M, 100Y, and 100K. The distance h (see FIG. 7) between the nozzle surface 33 and the nozzle surface 33 is adjusted. Here, the pressing force between the nozzle

surface wiping devices

100C, 100M, 100Y, and 100K and the ink jet heads 32C, 32M, 32Y, and 32K's nozzle surface 33 has a second pressing force larger than the first pressing force. Set to Here, the distance to be the second pressing force is a distance h ₂ (an example of a second distance). The distance _{h 2} is a distance _{h 1} is less than. Pressing force adjusting unit 158, the nozzle surface wiping device 100C, sets 100M, 100Y, and support 112 and the inkjet head 32C of 100K, 32M, 32Y, and the distance between the nozzle surface 33 of the 32K each distance _{h 2.}

Next, in step S6, the head movement control unit 150 controls the head moving unit 36 to move the inkjet heads 32C, 32M, 32Y, and 32K faster than the first speed from the image recording position toward the maintenance position. Move at speed. Here, the second velocity is 40 mm / s.

In step S7, the cleaning control unit 154 causes the web conveying unit 102 of the nozzle

surface wiping devices

100C, 100M, 100Y, and 100K to convey the wiping web 104. Here, the transport speed of the wiping web 104 is 3 mm / s.

Further, the cleaning control unit 154 controls the cleaning liquid deposition units 130 of the nozzle

surface wiping devices

100C, 100M, 100Y, and 100K, applies cleaning liquid to the wiping web 104, and brings the wiping web 104 into a wet state.

Here, the absorption amount per unit area of the wiping web 104 is 0.2 mg / mm ² (milligrams per square millimeter), the transport speed of the wiping web 104 is 3 mm / s, and the width of the wiping web 104 (direction orthogonal to the transport direction Length) is 45 mm (millimeters), and the absorption of the wiping web 104 is 0.2 × 3 × 45 = 27 mg / s (milligrams per second).

On the other hand, the application amount of the cleaning liquid by the cleaning liquid application unit 130 is 50 mg / s. That is, an amount exceeding the amount that the wiping web 104 can absorb is applied. Note that the wiping web 104 in the wet state is not limited to the state where the cleaning liquid in an amount larger than the absorbable amount is applied, but the cleaning liquid is applied to such an extent that the dirt and mist adhering to the nozzle surface 33 can be removed. It may be in a state as well.

surface wiping devices

100C, 100M, 100Y, and 100K, the nozzle surfaces 33 are wiped by the wiping webs 104. That is, the nozzle faces 33 of the ink jet heads 32C, 32M, 32Y, and 32K are respectively wiped wet by the second pressing force by the wiping web 104 in a wet state (an example of the second wiping mode).

FIG. 11 is a schematic view showing wet wiping. In wet wiping, wiping is performed to remove dirt on the nozzle surface 33 by the wiping web 104 in a wet state. No ink droplets remain on the nozzle surface 33 of the head 32 due to the dry wiping in step S4. Therefore, the ink droplets do not enter the gaps G between the head modules 200 adjacent to each other. For this reason, the nozzle surface 33 can be wiped with relatively strong pressing force.

In the dry wiping in step S4, the inkjet heads 32C, 32M, 32Y, and 32K are moved at a relatively low first speed in order to absorb the ink droplets on the nozzle surface 33 by the wiping web 104. On the other hand, in the wet wiping, wiping is performed by moving the inkjet heads 32C, 32M, 32Y, and 32K at a relatively high second speed. In the present embodiment, the transport speed of the wiping web 104 is the same for dry wiping and wet wiping, but depending on the absorption performance of the wiping web 104, the transport speed for dry wiping is relative to that for wet wiping. It is also possible to make the speed extremely slow.

When the first wet wiping is completed, the cleaning control unit 154 moves the nozzle surface wiping unit 82 to the retracted position, and the head movement control unit 150 moves the inkjet heads 32C, 32M, 32Y, and 32K from the maintenance position to the image recording position Move to the direction.

Next, in step S8, the pressing force adjustment unit 158 of the cleaning control unit 154 moves the nozzle surface wiping unit 82 to the wiping position, and the support base 112 for each of the nozzle

surface wiping devices

100C, 100M, 100Y, and 100K. and adjusting the distance between the nozzle surface 33 at a distance h _2, sets the pressing force of the wiping web 104 and the nozzle surface 33 in the second pressing force.

The head movement control unit 150 also controls the head moving unit 36 to move the inkjet heads 32C, 32M, 32Y, and 32K at a second speed from the image recording position to the maintenance position.

In step S9, the cleaning control unit 154 causes the web conveying unit 102 of the nozzle

surface wiping devices

100C, 100M, 100Y, and 100K to convey the wiping web 104. Here, the cleaning control unit 154 applies the cleaning liquid to the wiping web 104 to bring the wiping web 104 into a wet state.

In this state, when the inkjet heads 32C, 32M, 32Y, and 32K reach the positions facing the nozzle

surface wiping devices

100C, 100M, 100Y, and 100K, the nozzle faces 33 of the inkjet heads 32C, 32M, 32Y, and 32K. Are respectively wiped by the wiping webs 104. That is, each nozzle surface 33 is wiped wet by the second pressing force by the wiping web 104 in a wet state (an example of the third wiping mode).

Thus, the cleaning of the inkjet heads 32C, 32M, 32Y, and 32K is completed.

Here, the cleaning method immediately after the ink jet heads 32C, 32M, 32Y, and 32K perform the pressure purge at the maintenance position has been described, but in the ink jet recording apparatus 10, the ink jet heads 32C, 32M, 32Y, and 32K are images Immediately after image recording is performed on the sheet P at the recording position, and immediately after the inkjet heads 32C, 32M, 32Y, and 32K perform preliminary ejection at the maintenance position, dry wiping is not performed, and wet wiping is performed.

That is, when the ink jet recording apparatus 10 wipes a large amount of liquid ink droplets remaining on the nozzle surface after pressurized purge, the dry wiping mode is selected, and a small amount of solid ink adhered and dried on the nozzle surface by printing. When wiping off the mist, the wet wiping mode is selected (an example of the selection process). The ink jet recording apparatus 10 selects the dry wiping mode when the residual amount of ink on the nozzle surface 33 of the inkjet heads 32C, 32M, 32Y, and 32K is relatively large, and the residual amount of ink on the nozzle surface 33 is If the number is relatively small, the wet wiping mode may be selected.

<Evaluation of wiping performance and ink intrusion into the gap>
Under the following conditions, evaluation was made on the wiping performance and the ink penetration into the gap.

Dispense web material: Polyester Ink: Fuji Film Co., Ltd. C-WP-QM (Magenta)
Liquid discharge head: Fujifilm Dimatix Samba
Head configuration: Connect 17 modules to configure one inkjet head, 0.3mm gap between modules
The classification of each evaluation result is as follows.

A: Good B: Some problems C: Problems [Dispersibility of wet wiping]
Wet wiping of the nozzle surface 33 was performed using the pressing force between the wiping web 104 and the nozzle surface 33 as a parameter, and the wiping performance was evaluated from the amount of mist remaining on the nozzle surface 33. The amount of mist on the nozzle surface 33 before wiping was 20,000 to 30,000 pieces / mm ² (pieces per square millimeter).

The evaluation results are shown in Table 1. The amount of residual mist was measured by observing the area of 5 mm ² of four places of the nozzle surface 33 after wiping with a microscope.

As shown in Table 1, it was found that it is preferable to wipe with a pressure of 20 k to 60 kPa (kilopascals) or less.

[Delivery property of dry wiping and ink intrusion into gap]
The dry wiping of the nozzle surface 33 after pressurized purge was performed using the pressing force between the wiping web 104 and the nozzle surface 33 as a parameter, and the wiping property was evaluated from the amount of purge ink remaining on the nozzle surface 33. The evaluation results are shown in Table 2. In addition, the amount of remaining ink was measured by absorbing the nozzle surface 33 after wiping by the absorber for evaluation, and measuring the mass of the absorber for evaluation.

As shown in Table 2, the dry wiping after the pressure purge was good, the residual ink amount was 5 mg (milligram) or less per module regardless of the pressing force.

In the above, evaluation of the gap ink penetration was performed based on the amount of ink that got into the gap between the head modules 200. The evaluation results are shown in Table 3. In addition, the amount of penetration | invasion ink was measured by making the absorber for evaluation absorb the space | gap penetration | invasion ink after wiping off, and measuring the mass of the absorber for evaluation.

As shown in Table 3, when the pressing force is large, the amount of intruding ink increases. It was found that it is preferable to wipe with a pressure of 0 to 15 kPa for dry wiping after pressurized purge because the amount of ink entering the gap is small.

Here, the pressure of 0 kPa is defined as a state where the distance between the nozzle surface 33 and the wiping web 104 is 0 and the pressure is 0 kPa. That is, the nozzle surface 33 and the wiping web 104 are in contact with each other but no pressure is applied.

<Evaluation of liquid repellent film deterioration>
Under the following conditions, deterioration of the liquid repellent film on the nozzle surface 33 was evaluated.

Dispense web material: Polyester Ink: Made by FUJIFILM Corporation Cyan: C-WP-QC, Magenta: C-WP-QM, Yellow: C-WP-QY, Black: C-WP-QK
Liquid Ejection Head: Plate made of the same material as the nozzle surface for Samba manufactured by Fujifilm Dimatix Under this condition, by wiping each nozzle surface 33 with the wiping web 104 that has absorbed ink of each color and made it wet, pressure purge is performed. The state in which the dry wiping was performed in a state where the nozzle surface 33 was wet with the ink was simulated and simulated, and the number of times of wiping until the contact angle decreased to 60 °, which is a standard of the head life, was measured. The evaluation results are shown in Table 4.

As shown in Table 4, in the cyan, magenta, and yellow inks, there was no dependence of the pressing force after wiping 200,000 times or more, and no deterioration of the liquid repellent film was observed.

On the other hand, it was found that with black ink, the lower the pressing force, the more the number of times of wiping until the contact angle decreases to 60 °, which is an indicator of the head life. That is, the lower the pressing force, the longer the life of the liquid repellent film when wiping is repeated with the same frequency. This is because the pigment contained in the black ink has an abrasion effect.

As shown in Table 4, the pressing force of the wiping web 104 at the time of dry wiping the nozzle surface 33 of the inkjet head 32K is preferably 15 kPa or less, and more preferably 10 kPa or less. It is considered that the deterioration reducing effect of the liquid repellent film is enhanced as it approaches 0.

From the above results, the first pressing force, which is the pressing force between the nozzle

surface wiping apparatus

100C, 100M, and 100Y in the dry state and the ink jet heads 32C, 32M, and 32Y nozzle surface 33, is set to 0 to 15 kPa. It turned out that it is preferable to do. That is, in the case of dry wiping, a pressing force of 0 to 15 kPa is a desirable range for preventing entry of ink between the head modules and for appropriately wiping the nozzle surface.

The second pressing force, which is the pressing force between the nozzle

surface wiping devices

100C, 100M, 100Y, and 100K in the wet state and the nozzle surfaces 33 of the inkjet heads 32C, 32M, 32Y, and 32K, is 20 k to 60 kPa. It turned out that it is preferable to That is, in the case of the wet wiping, a pressing force of 20 k to 60 kPa is a desirable range for removing the ink mist which is generated in printing and dried and fixed and which can be fixed and to suppress the abrasion of the liquid repellent film.

Furthermore, it was found that it is preferable to set the third pressing force, which is the pressing force between the dry wiping web 104 of the nozzle surface wiping apparatus 100K and the nozzle surface 33 of the inkjet head 32K, to 0 to 10 kPa. That is, in dry wiping of the ink jet head 32 K that discharges black ink, a pressing force of 0 to 10 kPa is a desirable range for suppressing the abrasion of the liquid repellent film. Preferably, the third pressing force is a pressing force smaller than the first pressing force.

<Other Aspects of Nozzle Surface Cleaning Unit>
FIG. 12 is a front view showing the configuration of the main part of the ink jet recording apparatus 10 provided with the nozzle surface cleaning unit 90. As shown in FIG. The nozzle surface cleaning unit 90 includes a nozzle surface wiping unit 82 and a nozzle surface wiping unit 86.

The nozzle surface wiping unit 82 and the nozzle surface wiping unit 86 are arranged side by side in the moving direction (X direction) of the inkjet heads 32C, 32M, 32Y, and 32K. The nozzle surface wiping unit 82 may be disposed on the maintenance position side, and the nozzle surface wiping unit 86 may be disposed on the image recording position side. The nozzle surface wiping unit 82 and the nozzle surface wiping unit 86 wipe the nozzle surfaces 33 when the inkjet heads 32C, 32M, 32Y, and 32K move between the image recording position and the maintenance position, respectively.

The nozzle surface wiping unit 86 includes nozzle

surface wiping devices

100C, 100M, 100Y, and 100K that individually wipe the nozzle surfaces 33 of the inkjet heads 32C, 32M, 32Y, and 32K provided in the head unit 30. The nozzle

surface wiping devices

100C, 100M, 100Y, and 100K are installed on a common mount 88 according to the installation intervals of the inkjet heads 32C, 32M, 32Y, and 32K. The configuration of the nozzle

surface wiping devices

100C, 100M, 100Y, and 100K of the nozzle surface wiping unit 86 is the same as that of the nozzle surface wiping device 100 shown in FIG.

Here, the nozzle

surface wiping devices

100C, 100M, 100Y, and 100K of the nozzle surface wiping unit 82 (an example of the drying wiping unit) wipe the nozzle surfaces 33 of the inkjet heads 32C, 32M, 32Y, and 32K in the dry wiping mode. Do. That is, the nozzle

surface wiping devices

100C, 100M, 100Y, and 100K of the nozzle surface wiping unit 82 cause the wiping web 104 in contact with the nozzle surface 33 to be in a dry state by stopping the application of the cleaning liquid by the cleaning liquid application unit 130. .

On the other hand, the nozzle

surface wiping devices

100C, 100M, 100Y and 100K of the nozzle surface wiping unit 86 (an example of the wet wiping unit) wipe the nozzle surface 33 of the inkjet heads 32C, 32M, 32Y and 32K in the wet wiping mode. . That is, the nozzle

surface wiping devices

100C, 100M, 100Y, and 100K of the nozzle surface wiping unit 86 wet the wiping web 104 in contact with the nozzle surface 33 by the cleaning liquid deposition unit 130.

Similar to the nozzle surface wiping unit 82, the nozzle surface wiping unit 86 wipes the nozzle surfaces 33 when the inkjet heads 32C, 32M, 32Y, and 32K move to a position facing the nozzle surface wiping unit 86. A movement mechanism (not shown) is configured to be movable between the position and the retracted position in which each nozzle surface 33 is not wiped.

In the dry wiping mode, the nozzle surface wiping unit 82 moves to the wiping position, and the nozzle surface wiping unit 86 moves to the retracted position. On the other hand, in the wet wiping mode, the nozzle surface wiping unit 82 moves to the retracted position, and the nozzle surface wiping unit 86 moves to the wiping position. By moving in this manner, the nozzle surfaces 33 of the ink jet heads 32C, 32M, 32Y, and 32K can be dry wiped or wet wiped.

The nozzle surface wiping unit 82 may be used for wet wiping, and the nozzle surface wiping unit 86 may be used for dry wiping.

<Others>
The above cleaning method can be configured as a program for causing a computer to realize each process, and can also configure a non-temporary recording medium such as a CD-ROM (Compact Disk-Read Only Memory) storing the program. It is.

In the embodiment described above, for example, hardware of a processing unit that executes various processes such as the head movement control unit 150, the image recording control unit 152, the cleaning control unit 154, and the maintenance control unit 160. The structure is various processors as shown below. It is possible to change the circuit configuration after manufacturing a central processing unit (CPU) or a field programmable gate array (FPGA) that is a general-purpose processor that executes software (program) and functions as various processing units for various processors. Logic circuits (Programmable Logic Devices: PLDs), ASICs (Application Specific Integrated Circuits), etc., including dedicated electric circuits, etc., which are processors having a circuit configuration specifically designed to execute specific processing. Be

One processing unit may be configured by one of these various processors, or may be configured by two or more processors of the same type or different types (for example, a plurality of FPGAs or a combination of a CPU and an FPGA) May be In addition, a plurality of processing units may be configured by one processor. As an example in which a plurality of processing units are configured by one processor, first, one processor or more is configured by a combination of one or more CPUs and software as represented by computers such as servers and clients. There is a form in which a processor functions as a plurality of processing units. Second, as typified by a system on chip (SoC) or the like, there is a form using a processor that realizes the functions of the entire system including a plurality of processing units in one integrated circuit (IC) chip. is there. As described above, the various processing units are configured using one or more of various processors as a hardware structure.

Furthermore, the hardware-like structure of these various processors is more specifically an electric circuit (circuitry) combining circuit elements such as semiconductor elements.

The technical scope of the present invention is not limited to the scope described in the above embodiment. The configuration and the like in each embodiment can be appropriately combined among the embodiments without departing from the spirit of the present invention.

DESCRIPTION OF SYMBOLS 10 inkjet recording apparatus 20 paper conveyance part 22 belt 30 head unit 32 head 32C inkjet head 32K inkjet head 32M inkjet head 32Y inkjet head 33 nozzle surface 34 head support frame 36 head moving part 50 maintenance part 52 cap 52C cap 52K cap 52M cap 52Y Cap 54 waste liquid tray 56 waste liquid collection piping 58 waste liquid tank 80 nozzle surface cleaning unit 82 nozzle surface wiping unit 84 pedestal 86 nozzle surface wiping unit 88 pedestal 90 nozzle surface cleansing unit 100 nozzle surface wiping device 100C nozzle surface wiping device 100K nozzle surface wiping device 100M nozzle surface wiping device 100Y nozzle surface wiping device 102 web conveyance unit 104 wiping web 106 supply shaft 108 take-up shaft 11 Press roller 112 Support base 114 Spring 116 First guide roller 118 Second guide roller 120 Take-up motor 130 Wash solution application unit 132 Wash solution supply nozzle 134 Wash solution tank 136 Wash solution channel 138 Wash solution pump 150 Head movement control unit 152 Image recording control unit 154 Cleaning control unit 156 Selection unit 158 Pressure adjustment unit 160 Maintenance control unit 162 Pressure purge control unit 200 Head module 200-1 Head module 200- (i-1) Head module 200-i Head module 200- (i + 1) Head module 200-n head module 202 nozzle G gap P paper S1 to S9 process of processing liquid cleaning head cleaning method

Claims

A liquid discharge head for discharging a liquid from a nozzle disposed on a nozzle surface, comprising a plurality of head modules, and pressurizing the inside of the liquid discharge head having a gap between adjacent head modules to press the nozzle from the nozzle A pressure purge control unit that performs pressure purge to discharge liquid;
After the pressure purge is performed, a long wiping web in a dry state is brought into contact with the nozzle surface of the liquid ejection head with a pressing force of 0 kPa or more and 15 kPa or less, and the wiping is performed on the liquid ejection head A cleaning unit having a first wiping mode for transporting the web in the web transport direction to wipe the nozzle surface;
Liquid discharge head cleaning device equipped with
The cleaning unit brings the elongated wiping web in a wet state by the cleaning liquid into contact with the nozzle surface of the liquid ejection head with a pressing force of 20 kPa or more and 60 kPa or less, and the wiping web against the liquid ejection head. The liquid ejection head cleaning apparatus according to claim 1, further comprising a second wiping mode in which the nozzle surface is wiped by being conveyed in the web conveyance direction.
The cleaning unit is
The wiping web in the dry state is brought into contact with the nozzle surface of the liquid discharge head via the contact member with a pressing force of 0 kPa or more and 15 kPa or less, and the contact member is relative to the liquid discharge head A drying and wiping unit that moves and wipes the nozzle surface;
The wiping web in the wet state is brought into contact with the nozzle surface of the liquid discharge head via a contact member with a pressing force of 20 kPa or more and 60 kPa or less, and the contact member is relative to the liquid discharge head A wet wiping unit that moves to wipe the nozzle surface;
A cleaning control unit that causes the nozzle surface to be wiped by the dry wiping unit in the first wiping mode, and that the nozzle surface is wiped by the wet wiping unit in the second wiping mode;
The liquid discharge head cleaning apparatus according to claim 2, further comprising:
The cleaning unit is
A wiping unit for bringing a wiping web into contact with a nozzle surface of the liquid discharge head via a contact member, and moving the contact member relative to the liquid discharge head to wipe the nozzle surface;
A pressing force adjustment unit that adjusts the pressing force between the nozzle surface and the wiping web;
A cleaning solution application unit for applying a cleaning solution to the wiped web in a dry state to make it wet;
In the first wiping mode, the cleaning fluid deposition unit is inoperative and the dry wiping web is brought into contact with the nozzle surface with a pressing force of 0 kPa or more and 15 kPa or less, and in the second wiping mode, the cleaning fluid deposition unit A cleaning control unit for applying the cleaning solution to bring the wiping web in the wet state into contact with the nozzle surface with a pressing force of 20 kPa or more and 60 kPa or less;
The liquid discharge head cleaning apparatus according to claim 2, further comprising:
The cleaning unit is
An elastic member biasing the contact member in a first direction toward the nozzle surface;
A support portion for supporting the elastic member;
Equipped with
The cleaning control unit, in the first wiping mode, sets the distance in the first direction between the support unit and the nozzle surface such that the pressing force between the nozzle surface and the wiping web is 0 kPa or more and 15 kPa or less. The distance between the support portion and the nozzle surface in the first direction is set to a pressing force of 20 kPa or more and 60 kPa or less in the second wiping mode. The liquid discharge head cleaning apparatus according to claim 4, wherein the second distance is a pressure.
The cleaning unit is
A long wiping web moistened by the cleaning liquid is brought into contact with the nozzle surface of the liquid ejection head with a pressing force of 20 kPa or more and 60 kPa or less, and the wiping web is moved against the liquid ejection head in the web conveying direction. And a third wiping mode for conveying and wiping the nozzle surface;
6. The method according to claim 2, wherein the wiping in the second wiping mode is performed after the wiping in the first wiping mode, and the wiping in the third wiping mode is performed after the wiping in the second wiping mode. The liquid discharge head cleaning device according to the above.
A liquid discharge head for discharging a liquid from a nozzle disposed on a nozzle surface, comprising a plurality of head modules and having a gap between the adjacent head modules A first wiping mode for bringing the wiping web into contact with the liquid ejection head in the web conveyance direction to wipe the nozzle surface by bringing the wiping web into contact with a pressing force of 0 kPa or more and 15 kPa or less; A long wiping web moistened by the cleaning liquid is brought into contact with the nozzle surface of the ejection head with a pressing force of 20 kPa or more and 60 kPa or less, and the wiping web is transported in the web conveyance direction with respect to the liquid ejection head. A cleaning unit having a second wiping mode for wiping the nozzle surface;
A selection unit that selects one of the first wiping mode and the second wiping mode;
Liquid discharge head cleaning device equipped with
A liquid discharge head for discharging a liquid from a nozzle disposed on a nozzle surface, comprising a plurality of head modules, and having a gap between adjacent head modules,
A transport unit for transporting the recording medium;
A recording control unit configured to cause the nozzle of the liquid discharge head to eject the liquid onto the recording medium to be conveyed to record an image on the recording medium;
A pressure purge control unit that performs pressure purge to press the inside of the liquid discharge head and discharge the liquid from the nozzle;
After the pressure purge is performed, a long wiping web in a dry state is brought into contact with the nozzle surface of the liquid ejection head with a pressing force of 0 kPa or more and 15 kPa or less, and the wiping is performed on the liquid ejection head A cleaning unit having a first wiping mode for transporting the web in the web transport direction to wipe the nozzle surface;
Liquid discharge device equipped with
It has a plurality of liquid ejection heads that eject different colors of ink,
The cleaning unit is configured to wipe a pressing force when wiping the liquid ejection head that ejects black ink in the first wiping mode when wiping the liquid ejection head that ejects ink other than the black ink. The liquid discharge device according to claim 8, wherein the pressing force is smaller than the pressing force.
A liquid discharge head for discharging a liquid from a nozzle disposed on a nozzle surface, comprising a plurality of head modules, and pressurizing the inside of the liquid discharge head having a gap between adjacent head modules to press the nozzle from the nozzle A pressurized purge step of pressurized purge for discharging the liquid;
After the pressure purge is performed, a long wiping web in a dry state is brought into contact with the nozzle surface of the liquid ejection head with a pressing force of 0 kPa or more and 15 kPa or less, and the wiping is performed on the liquid ejection head A cleaning step of conveying the web in the web conveyance direction to wipe the nozzle surface;
A method of cleaning a liquid discharge head comprising:
A liquid discharge head for discharging a liquid from a nozzle disposed on a nozzle surface, comprising a plurality of head modules and having a gap between the adjacent head modules A first wiping mode for bringing the wiping web into contact with the liquid ejection head in the web conveyance direction to wipe the nozzle surface by bringing the wiping web into contact with a pressing force of 0 kPa or more and 15 kPa or less; A long wiping web moistened by the cleaning liquid is brought into contact with the nozzle surface of the ejection head with a pressing force of 20 kPa or more and 60 kPa or less, and the wiping web is transported in the web conveyance direction with respect to the liquid ejection head. A second wiping mode for wiping the nozzle surface;
A selection step of selecting one of the first wiping mode and the second wiping mode;
A method of cleaning a liquid discharge head comprising: